Overview

Product details

The XB431-LM is a precision 1.24 V shunt regulator capable of regulating to 30 V. Negative feedback from the cathode to the ADJUST pin controls the cathode voltage, much like a non-inverting op amp configuration. A dual resistor divider terminated at the ADJUST pin controls the gain of the 1.24 V bandgap reference voltage. Shorting the cathode to the ADJUST pin (voltage follower) provides a 1.24 V cathode voltage.

The XB431-LM has an initial tolerance of 1.0% and is functionally suitable for several applications requiring Zener diode type low voltage performance. Applications include bypassing 3 V to 2.7 V low dropout regulators, error amplifiers in 3 V off-line switching regulators and even as a voltage detector.